Habitat Model Or Urban-Nesting Cooper's Hawks (Accipiter Cooperii) in Southern Arizona (Report‪)‬

Birds of prey, including kites, hawks, falcons, owls, and eagles, have become increasingly common in urban landscapes over the past 3 decades (Adams, 1994; Gehlbach, 1994; Smith et al., 1999; Anderson and Plumpton, 2000; Mannan and Boal, 2004; Chace and Walsh, 2006). Predatory birds in landscapes dominated by people create situations beneficial or problematic to both birds and people. For example, urban landscapes can provide high-quality habitat for birds of prey; however, in some settings, urban-related problems such as electrocution, disease, and collisions with windows and cars can reduce rates of survival and productivity of raptors (Mannan and Boal, 2004). For most people, the opportunity to see predatory birds near their homes is viewed positively because of aesthetic and educational benefits (Mannan and Boal, 2004). However, aggressive behavior toward people and household pets by predatory birds defending their nests can result in negative reactions by people. Accumulation of remains of prey and fecal matter is a nuisance in some circumstances. Significant economic impact can arise if a species, protected under environmental legislation (e.g., Endangered Species Act), is in an area undergoing development. Thus, knowledge of conditions that trigger predatorybirds to settle in towns and cities can assist city planners and individual residents in making choices to encourage or discourage their presence. Cooper's hawks (Accipiter cooperii) breed throughout the United States, southern Canada, and northern Mexico. They occur in a diversity of forested or riparian areas (Rosenfield and Bielefeldt, 1993), but also are in suburban and urban areas throughout the United States (Bosakowski and Smith, 1997; Boal and Mannan, 1998; McConnell, 2003; DeCandido and Allen, 2005). Evidence from southern Texas and northeastern Mexico suggests expansion southward in urban areas (Brush, 2008). To better understand where Cooper's hawks nest in urban environments in southern Arizona, we used data from nesting and random sites in Tucson to develop a model for predicting the probability of occurrence of nesting Cooper's hawks in other urban areas. We then tested the model in three cities near Tucson. Surveys conducted while testing the model also provided an initial assessment of the number and distribution of nesting Cooper's hawks in selected urban areas in southern Arizona.